Automatic Ventilation in Minimal Flow Anaesthesia

Summary

A number of ventilators including Pulmomat 19.1, Spiromat 650, Ventilog, and AV-1 were studied with respect to their use in minimal flow anaesthesia. It was shown that using fresh gas flows of 300 ml O2 and 200 ml N2O per minute the new ventilators can be used in minimal flow anaesthesia. Respiratory characteristics and respiratory volumes remain roughly constant.

Due to lekages and a lack of precise rotameters none of the ventilators included in this trial are suitable for closed-circuit anaesthesia.